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Turbo M50B32 Knocking

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Hey all, I just built a fresh M50B32 with JE pistons, K1 rods, new everything else, and a GTW3684R 0.82A/R; running on Pump 93 (US). The engine has about 300 miles on it at this point, and a compression test yields about 135-145psi across all cylinders. I have not done a leakdown but I figured the compression was good so I left it.

I'm using a Link G4+ KnockBlock to listen for knock, I previously had a single knock sensor for the device on the lower side of the block and have since installed both sensors in the stock locations near the deck of the block. With my airport earbuds and 3M Peltor earmuffs, I can hear, what sounds to me, like knock around peak torque. I back off every single time I get near this area until I can sort out whether the knock is legit or not.

I can also hear what kind of sounds like pinging as RPM increases towards this area, but it doesn't seem to follow load very much, so I wrote that off as mechanical noise. I've yet to get the KnockBlock connected to my PCLink/Link G4+, but I'm just looking for some general opinions here. I reworked my ignition map, examples of areas are 14 degrees at 3500RPM and 140kpa, 13.5 degrees at 4000rpm and 150kpa, 12.5 degrees at 4300RPM and 150kpa. This is kind of the area where it sounds like legitimate knock. I didn't think that the ignition angle was too advanced, but I'm open to opinion.

If it's not the ignition timing, I'm not sure what it is. Maybe a clogged fuel injector and one cylinder is running leaner? My O2 in the downpipe reads a steady 11.5-11.8

EDIT: I haven't confirmed the timing with a timing light on this engine, but the same trigger wheel, sensors, and ECU were on the M52 I had in here before, and I had checked that engine with a timing light and it was dead on.

Far out man, check the base timing, that is the first thing you should do before tuning any engine.

If you are not sure if what you are hearing is knock, then remove 5deg of advance from the whole ign table and give it another run, if the noise disappears then it was knock.

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